Field of the Invention
The present invention relates to an imprint apparatus and a method of manufacturing an article.
Description of the Related Art
An imprint apparatus which forms a pattern on an imprint material on a substrate by using a mold having a pattern surface on which a pattern is formed has attracted attention as one of mass production lithography apparatuses for semiconductor devices and the like. The imprint apparatus cures an imprint material on a substrate while a mold is in contact with the imprint material, and separates the mold from the cured imprint material, thereby forming a concave-convex pattern on the imprint material on the substrate.
The imprint apparatus may make the “residual layer thickness of an imprint material” uniform on a substrate. This residual layer thickness indicates the thickness of the imprint material between the substrate and a concave portion of a concave-convex pattern formed on the imprint material. For this purpose, the relative inclination between the pattern surface of the mold and the surface of the substrate may be controlled so as to a target relative inclination (e.g., parallel) when bringing the mold into contact with the imprint material. Japanese Patent Laid-Open No. 2005-101201 discloses an example of a method of controlling the relative inclination between the pattern surface of a mold and the surface of a substrate based on a result obtained by measuring the inclination of the surface of the substrate.
With an increase in the complexity of the apparatus arrangement of an imprint apparatus, it is more difficult to arrange a measurement unit for measuring the inclination of the surface of a substrate near a contact position where a mold is brought into contact with an imprint material. Therefore, the measurement unit may be arranged such that the inclination of a substrate is measured at a position (measurement position) different from a contact position. The inclination of the surface of the substrate at the contact position can be controlled based on a measurement result obtained by measuring the inclination of the surface of the substrate using the measurement unit at the measurement position. However, for example, there is a case that the distortion of a base plate, on which a stage holding a substrate moves, is different between a contact position and a measurement position. In this case, controlling the inclination of the surface of the substrate at the contact position based on a measurement result obtained by the measurement unit arranged at the measurement position can make it difficult to accurately control the relative inclination between the pattern surface of a mold and the surface of the substrate.